1. Field of the Invention
The invention relates to an image display device and a method for manufacturing the same.
2. Description of the Related Art
Liquid crystal display devices mainly include a pair of substrates in which a liquid crystal is interposed therebetween and a back light, and include a display region in which a plurality of pixels are provided on principal surfaces of the pair of substrates. These pixels are configured to independently generate an electric field that drives liquid crystal molecules, whereby light transmittance corresponding to the driving of the liquid crystal molecules is obtained. Moreover, a liquid crystal display device in which glass substrates or plastic (resin) substrates are used as a pair of substrates, and a display surface having flexure property, that is, being configured to be bent easily is known. The liquid crystal display device having such a configuration has excellent impact resistance and flexibility, and commercialization thereof is much needed.
Particularly, in a liquid crystal display device in which a resin film FLM is used as a first substrate SUB1, a TFT layer TFTL is provided on the resin film FLM (the first substrate SUB1), as shown in FIG. 46. On the other hand, in a liquid crystal display device in which a plastic substrate is used as a first substrate SUB1, a resin film FLM is provided between the first substrate SUB1 and the TFT layer TFTL, as shown in FIG. 47. In the liquid crystal display devices shown in FIGS. 46 and 47, properties of thin film transistors in the TFT layer TFTL change greatly due to the effect of moisture and oxygen penetrating through the plastic substrate and the resin film serving as the first substrate SUB1. Therefore, in the liquid crystal display device of the related art, as shown in FIG. 48, a barrier layer BRF is provided between the first substrate SUB1 and the resin film FLM and between the resin film FLM and the TFT layer TFTL to thereby block moisture, oxygen, and the like penetrating through the first substrate SUB1 formed of the plastic substrate which is a resin member and the resin film FLM. Thus, it is possible to prevent the moisture, oxygen, and the like from affecting the properties of the thin film transistors formed in the TFT layer TFTL. As a resin film used in the liquid crystal display device having such a configuration, a transparent conductive film disclosed in JP-9-254303A is known, for example.
In manufacturing of an image display device having a liquid crystal display device, thin film transistors, electrodes, and the like necessary for forming a plurality of display devices are formed on one of a pair of substrates called mother substrates, and color filters and the like are formed on the other mother substrate. Thereafter, the pair of mother substrates are fixed by a sealing material to thereby form the plurality of display devices (hereinafter referred to as unit display devices) in the pair of mother substrates, and then, the mother substrates are cut to be divided into the unit display devices, whereby a plurality of liquid crystal display devices are manufactured at one time.
However, in manufacturing of the liquid crystal display device by such a method, side surfaces (edge portions or cutting surfaces) of the plastic substrate and the resin film on which the barrier layer is formed are exposed to the atmosphere. Therefore, it is difficult to block moisture and oxygen from the side surfaces of the plastic substrate and the resin film. Thus, there is a possibility that the properties of the thin film transistors formed on the TFT layer change greatly.